Under British law, the burden of proof is on the defendant to prove that a statement was true.

In America, the burden is on the plaintiff, the result of the landmark 1964 Supreme Court case "New York Times vs. Sullivan," which required public figures who are suing news organizations for libel to prove that false information was published knowingly and with malicious intent.

Trump's comments last year unsettled much of the news media, and journalists were similarly irritated by his tweet on Thursday.

But it wouldn't be easy for Trump to "change" or "open up" the laws. For one thing, there is no single law that could be changed, other than the First Amendment and the protections it gives. Libel laws vary by state; there is no federal libel law.

A White House spokeswoman did not respond to an inquiry seeking more information on the president's thinking.

Trump's tweet was his second attack on the "failing" New York Times in as many days. On Wednesday, he falsely claimed that the newspaper "apologized to its subscribers, right after the election, because their coverage was so wrong." In fact, the Times made no apology.

On Thursday, Trump tweeted out a three-day old column published by the New York Post's John Crudele, who wrote that he canceled his subscription to the Times due to what he said was dishonest coverage of the president.

Last month, First Lady Melania Trump settled her own defamation lawsuit against a Maryland blogger who wrote that she used to be involved in a "high-end escort" service.

She had also sued the parent company of the British tabloid the Daily Mail for publishing the same claim.

The Daily Mail retracted its story after the lawsuit was filed, and the case was tossed last month over jurisdictional issues. The first lady refiled the lawsuit days later.

CNNMoney (New York) First published March 30, 2017: 12:00 PM ET

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